Scientists consider Oregano (Origanum vulgare L.) as the leading spice plant for antioxidant production and its antioxidant amounts show noteworthy diversity among various plant variations. The research examined in vitro antioxidant capacities of oregano plants (Origanum vulgare) along with their chemical substance profile determination. Researchers at 4 °C macerated 10 g of aerial-dried flowered parts in a 250 mL solution containing 50% ethanol by volume mixed with water until the extraction process reached 24 hours before gravity filtration. The extractive process was conducted four times to obtain maximum compounds before rotary-evaporation condensed the solution. This work identified seventeen metabolites by (GC-MS) beta-Terpinene, (+)-piperitol, 5-Isopropyl-2-methylphenol, Limonene, 2-Isopropyl-5-methylphenol, Linalool, beta-Ocimene, 1-octanol, Geraniol, Thujene, Thymol methyl ether, Sabinen, beta-Myrcene and 1-p-Menthene-8-thiol. Antioxidant activity (Singlet oxygen scavenging) of Leaves extract (Ethyl acetate, Ethanol and Gallic acid (standard)) of Origanum vulgare recorded 74.82 ± 3.70, 66.31 ± 3.68, 58.18 ± 3.40, 52.67 ± 3.32, 57.04 ± 3.37, and 51.84 ± 2.91 respectively. While recorded 114.55 ± 5.41, 125.06 ± 6.08, 112.44 ± 5.97, 140.05 ± 5.42, 150.17 ± 6.27, and 215.72 ± 8.15 respectively. Even after advancements in pharmaceutical sciences, medicinal plants are used to prevent and cure a broad range of diseases due to their exceptional nutraceutical and therapeutic properties. Origanum vulgare is a medicinal plant with numerous therapeutic benefits.